Today, industrial robots are mostly single-arm robots. A typical single-arm robot has a plurality of joints (e.g. six or more joints) but only one single kinematic chain. On the robot kinematic chain, usually at its end, it is mounted an industrial tool for performing a robotic task. Examples of robotic tasks performed by tools include, but are not limited to, welding, spot welding, arc welding, painting, coating, drilling and riveting, laser cutting, hemming, and other types of manufacturing operation tasks performed by tools). The end of the robot kinematic chain may also be known as Tool Center Point Frame (“TCPF”) or Tool Center Point (“TCP”).
Robots belonging to the new generation of industrial robots are called twin robots. A twin robot has a plurality of joints (e.g. eight or more joints) and it has two kinematic chains. At the end of each kinematic chain it is mounted an industrial tool.
The twin robot is also known in the art as dual TCP branch robot, dual TCP robot, dual arm robot, dual head robot, dual kinematic chain robot, and the like. Herein the term twin robot is used. An industrial robot having three kinematic chains is called a triplet robot. An industrial robot having N (with N>=2) kinematic chains is herein called a multiple robot. In the foregoing a twin robot is discussed but the skilled person easily appreciates that similar considerations apply to a robot having three or more kinematic chains.
With traditional “single-arm” robots, manufacturing facilities are required, in order to increase production throughput, to buy two or more robots, to use two or more robot controllers to synchronize between them in order to avoid collisions and to maintain two or more robots.
As a consequence, in order to reduce costs while keeping the same factory production levels, twin robots and, more generally, multiple robots are more and more used in replacement of two or more traditional single-arm robots.
Moreover, one twin robot can advantageously be used for replacing one traditional single arm robot. In fact a twin robot, by having two arms, can work in a freer and more flexible manner. In addition, the fact that two tools are mounted instead of one saves cycle time compared to one single-arm robot with a tool changer.
Techniques for off-line validations and virtual 3D environment simulations and for determining optimal robot configurations for industrial tasks are known.
However such techniques are aimed at robot scenarios having only one single kinematic chain and do not work for robots having two or more kinematic chains where the complexity is higher. Therefore, improved techniques are desirable.